It is not necessary to ground them all. If there are multiple strands, it is enough to ensure that the ground wires are all grounded. You can connect multiple strands of ground wires.
The following points should be paid attention to when grounding the computer cable shield:
(1) The control cable shield of the analog signal loop of the computer control system should be centralized One point grounding. The reason is based on the requirement to ensure the normal operation of the computer monitoring system, because even an interference voltage of only about 1V may cause fallacies in logical judgments. Centralized grounding can avoid ground circulation;
(2) In addition to computers Except for the situation where the control cable shielding layer of the monitoring system is only allowed to be grounded at one point, other control cable shielding layers should be grounded at two points when the electromagnetic induction interference is large, and at one point when the electrostatic induction interference is large;
(3) The inner shielding layer of double shielding or composite total shielding should be grounded at one point, while the outer shielding layer can be grounded at two points;
(4) When two-point grounding is selected, It should be considered that the shielding layer will not be burned under the action of transient current.